Abstract: The fluctuation of fertilization is generally caused by the uneven supply of fertilizer at the fertilizer outlet or the uneven discharge of fertilizer by the fertilizer applicator, which leads to the periodic change of the fertilizer amount during the fertilization operation, resulting in low fertilizer utilization rate, uneven nutrient distribution, soil compaction and other results. Aiming at the problem of fertilizer pulsation of corn precision seeder in the process of fertilizer application, this paper takes the fertilization device of corn precision seeder as the research object, and uses discrete element method to analyze the effects of three factors on fertilizer pulsation, including the rotation speed of spiral winch, the spiral lift angle of outer slot wheel and the angle of fertilizer tongue. The variation coefficient of stability of fertilizer discharge was selected as the evaluation index, and the simulation experiment was carried out according to quadratic regression orthogonal combination design. The results showed that the optimum parameter combination was 20 r/min rotation speed, 10° tongue angle and 75° screw rise angle, and the variation coefficient of stability of fertilizer discharge was 2.31%. In order to verify the accuracy of the simulation results, bench tests were carried out on the JPS-12 test bench under the optimal parameter combination. The results showed that the variation coefficient of stability of fertilizer discharge was 2.55%.

Key words:  , corn, precise fertilization, outer slot wheel fertilizer distributor, pulsation, helical strangler, DEM

摘要： 施肥脉动性一般由排肥口肥料供给不均匀或排肥器排肥不均匀引起，导致施肥作业中排肥量时大时小呈周期性变化，造成肥料利用率低、营养分布不均匀、土壤板结等结果。针对玉米精量播种机在种肥同施过程中施肥脉动性问题，以玉米精量播种机的施肥装置为研究对象，运用离散元法分析螺旋绞龙转速、外槽轮排肥器的螺旋升角以及排肥舌倾角3个因素对施肥脉动性的影响。选用排肥量稳定性变异系数作为评价指标，根据二次回归正交组合设计进行仿真试验。结果表明，最佳参数组合为螺旋绞龙转速20 r/min、排肥舌倾角10°、螺旋升角75°，此水平组合下的排肥量稳定性变异系数为2.31%。为验证仿真结果的准确性，使用JPS-12试验台在最佳参数组合下进行台架试验。台架试验结果表明，排肥量稳定性变异系数为2.55%。

关键词: 玉米, 精量施肥, 外槽轮排肥器, 脉动性, 螺旋绞龙, 离散元法